Just wondering if I am missing a step or doing something wrong.
edit: I'm starting to wonder if it's because I only have 1 'disk' in this VM, and perhaps the entire disk has been formatted to ufs and so I can't create a zpool on that disk? Do I need to add another disk in VMware?

Also, does anyone know what filesystems are natively supported in FBSD 6.x and 8.x? I believe 6.x supports ufs and 8.x supports ufs and zfs, but I am not positive.

I found my problem: I only had one disk, and I guess it was entirely allocated to my existing ufs filesystem. Once I added a new disk, I was able to specify it as the device and I was able to successfully create a zpool/zfs filesystem:

Also, does anyone know what filesystems are natively supported in FBSD 6.x and 8.x? I believe 6.x supports ufs and 8.x supports ufs and zfs, but I am not positive.

ZFS is a combined file system and logical volume manager originally designed by Sun Microsystems. It was ported to FreeBSD and has been part of the operating system since FreeBSD 7.0. FreeBSD 6.x use UFS.